JPH08132415A - Method and device for molding hydraulic inorganic molding - Google Patents

Abstract

PURPOSE: To obtain a dense molding, the void content of which is small and which has excellent strength, by a method wherein pressure is uniformly applied over the whole surface of a shaped matter under the condition that the temperature of the hydraulic inorganic molding material in a cavity is controlled to have the specified value. CONSTITUTION: A first split mold (or a bottom mold) and a second split mold (or a top mold) are closed together. Then, molding material is poured in a cavity, which is formed by the closure. By the material pouring, an elastic sheet 3, which is provided along the inner wall of the second split mold 2, is extended so as to come into close contact with the inner wall surface of the mold. The poured molding material is controlled to be kept within the temperature range of 20-50 deg.C. Next, by sucking through the drainage holes 11 of the first split mold, the water content in the hydraulic inorganic molding material is extracted. In addition, by forcing pressurizing medium 4 through a pouring pipe 22 between the second split mold 2 and the elastic sheet 3, a dense shaped matter is obtained.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for molding a hydraulic inorganic molded article and a molding apparatus used for carrying out this molding method.

[0002]

2. Description of the Related Art Conventionally, molding of a complicated shape has been performed by using a hydraulic inorganic molding material (hereinafter referred to as "molding material") whose main component is a hydraulic inorganic material such as cement, gypsum and calcium silicate forming material. To mold a product, for example, Japanese Patent Publication Sho 5
As disclosed in Japanese Patent Laid-Open No. 9-37202, a method of press-molding a molding material into a mold cavity and then dewatering excess water from a water drain hole formed in a mold wall surface through a filtering material to form a shape. Is taken.

However, in the above-mentioned method, pressure cannot be applied to the molding material in the mold cavity, so that the obtained molding has a drawback that the porosity is large and the strength of the base material is weak. There is. Therefore, the inventor of the present invention has previously developed a first split mold in which a large number of water drainage holes are formed in the wall surface and a second split mold in which an elastic sheet having airtightness is integrally provided at the peripheral edge along the inner wall surface. After the molding material is press-fitted into the mold cavity formed by closing and, the pressurizing medium is press-fitted between the elastic sheet and the inner wall surface of the second split mold to compress the molding material through the elastic sheet. At the same time, a hydraulic inorganic material characterized by performing a press-fitting dehydration step of dehydrating excess water of the molding material in the mold cavity out of the mold from the water draining hole of the first split mold to shape it into a desired shape. Molding method of molded article (Japanese Patent Laid-Open No. 5-2
Japanese Patent Laid-Open No. 00709) has been previously proposed.

That is, in this molding method, in addition to dehydrating the water in the molding material by suctioning through the water drain holes of the first split mold, a pressure medium is provided between the second split mold and the elastic sheet. By pressing, the elastic sheet is expanded to the molding material side in the mold cavity by the pressurizing medium and even pressure is applied to the entire surface of the molding material, and the molding material is compressed to facilitate dehydration and form a more precise shaped object. It had an excellent effect that it could be done.

[0005]

However, this method still has the following points to be improved. That is, in the conventional method described above, the temperature of the molding material is low, especially in the winter when the temperature is low, so that the temperature of the mold surface decreases every time the molding material is injected into the mold cavity. Then, when the temperature of the mold surface decreases, the viscosity of the molding material increases and the dehydration rate decreases, which requires extra dehydration time.

Therefore, as a result, the molding time required for each cycle becomes long and there is a problem that productivity is poor. INDUSTRIAL APPLICABILITY The present invention can apply pressure uniformly to the entire surface of a shaped article, and can obtain a dense and excellent molded product with small porosity, and of course, a hydraulic inorganic material excellent in productivity. It is an object of the present invention to provide a method for molding a molded article and a molding apparatus used for carrying out this molding method.

[0007]

In order to achieve such an object, a method of molding a hydraulic inorganic molded article according to the present invention comprises a first split mold having a large number of drainage holes on a wall surface and an airtight seal. Elastic sheet is integrated into the periphery and a second split die provided along the inner wall surface is closed to press the molding material into a mold cavity, and then the elastic sheet and the second split die are formed. A pressurizing medium is press-fitted between the inner wall surface of the mold and the molding material is compressed through the elastic sheet, and the first material is sucked.
In the molding method of the hydraulic inorganic molded article, which is formed into a desired shape by performing a press-fitting dehydration step of dehydrating excess water of the molding material in the mold cavity from the water removal hole of the split mold to the outside of the mold, The temperature of the molding material was adjusted to 20 to 50 ° C.

In the above structure, as a method for adjusting the temperature of the molding material in the mold cavity to 20 to 50 ° C., the molding material is heated to 20 to 50 ° C. in advance before the molding material is pressed into the mold cavity. Examples include a method of placing the mold, a method of heating the mold itself by a heating means, and the like. Further, the compression and the suction may be performed at the same time, but it is preferable that the suction is first performed and the compression is started after a predetermined time has elapsed.

The suction pressure is not particularly limited, but is -500.
It is preferably about mmHg. The compression pressure is not particularly limited, but is preferably about 5 kg / cm ² . In addition, it is preferable that the first split mold is provided with a filter material having extensibility along the inner wall thereof. The material of the filter medium is a material whose dimensions expand and expand when an external force is applied, and examples thereof include cloth using crimped yarn and porous rubber.

The molding material is mainly composed of a hydraulic inorganic material which is hardened by a hydration reaction such as cement, gypsum, calcium silicate forming material, sand, gravel as an aggregate, mineral fiber as a reinforcing material, and glass fiber. , A mixture of animal and plant fibers, synthetic fibers, semi-synthetic fibers, quick-hardening materials, pigments, etc., and materials that can be used in the production of general inorganic molded articles.

The pressurizing medium is not particularly limited, but examples thereof include liquids such as water and oil. Examples of the elastic sheet include materials having excellent airtightness and watertightness such as rubber. on the other hand,
The hydraulic inorganic molded article molding apparatus according to the present invention has a first split mold in which a large number of drainage holes for dehydrating excess water of a shaped object are formed in the wall surface, and an elastic sheet having airtightness integrates the peripheral edge. And a second split mold which is provided along the inner wall surface and is capable of injecting a pressure medium between the elastic sheet and the inner wall surface and which is closed with the first split mold to form a mold cavity having a desired shape. Then, in a molding apparatus for a hydraulic inorganic molded article, in which a molding material injection port to the mold cavity is provided on the side of the second split mold, the molding material for shaping the first split mold in the mold cavity is added. The heating means for heating is provided.

In the above construction, as the heating means, a method of embedding a heating wire in the second split mold and heating by the heating wire, a flow path through which the heating medium flows is provided inside the second split mold, and this flow path is used. Examples include a method of heating by heating with a heating medium. The injection port for the molding material may be provided at one place, but it is preferable to provide it at a plurality of places at the portion corresponding to the mouth surface of the formed product.

[0013]

According to the method of molding the hydraulic inorganic molded article of the present invention, first, the first split mold and the second split mold are closed. Then, the molding material is injected into the mold cavity formed by this closing. By this injection, the elastic sheet provided along the inner wall of the second split mold stretches and comes into close contact with the inner wall surface of the mold. In addition,
When the extensible filter medium is provided inside the first split mold, the filter medium also stretches and adheres to the inner wall surface of the first split mold. Therefore, the molding material is injected into a shape along the shape of the inner surface of the mold cavity. Moreover, the injected molding material is 20 to
The temperature is adjusted to a temperature of 50 ° C.

Next, in addition to dehydrating the water in the hydraulic inorganic molding material by suctioning through the water drain holes of the first split mold, a pressurizing medium is provided between the second split mold and the elastic sheet. When pressed, the elastic sheet swells toward the hydraulic inorganic molding material side in the mold cavity by the pressurizing medium and uniformly applies pressure to the entire surface of the hydraulic inorganic molding material to compress the water-soluble inorganic molding material and facilitate dehydration. .

Moreover, as described above, since the temperature of the molding material in the mold cavity is adjusted to 20 to 50 ° C., the viscosity of the molding material can be appropriately maintained, dehydration can be efficiently performed, and a dense shaped object can be obtained. Can be That is, when the temperature of the molding material is lower than 20 ° C., the viscosity increases and the dehydration rate decreases, and when the temperature of the molding material exceeds 50 ° C., the rapid hardening of the molding material is promoted, resulting in poor shapeability.

On the other hand, according to the apparatus for molding a hydraulic inorganic molded article of the present invention, the heating means provided in the first split mold heats the mold surface temperature of the first split mold to a predetermined temperature. Then, the molding material is injected into the mold cavity. The molding material pressed into the mold cavity is dehydrated and shaped by the first split mold while being kept at a desired temperature.

The temperature of the molding material in the mold cavity is set to 20 to 5
In order to maintain the temperature at 0 ° C, the temperature of the mold surface of the first split mold is set to 3
It is preferable to heat the mixture to 0 to 60 ° C. That is, when the temperature of the mold surface is lower than 30 ° C., it becomes difficult to keep the temperature of the molding material at 20 ° C. or higher, and when the temperature exceeds 60 ° C., the molding material undergoes rapid curing, which causes a problem in shapeability. There is a fear.

[0018]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described in detail below with reference to the drawings showing the embodiments thereof. (Examples 1 to 5) A molding apparatus A as shown in FIG. 1 was prepared. That is, this molding apparatus A includes a lower mold 1 as a first split mold having a length of 900 × a width of 500 × a height of 300 mm, and a second mold.
The upper mold 2 has a length of 900 × width of 500 × height of 300 mm as a split mold.

The lower mold 1 has a water drainage hole 1 with a diameter of 3 mm on its wall surface.
1 is bored at a pitch of 50 mm, and a heater tube 12 as a heating means is provided inside.
Water heated to a preset temperature passes through the heater tube 12 as a heating medium. The lower mold 1 is provided with a filter material 14 along the inner wall surface 13.

The upper mold 2 is provided with a bag-shaped elastic sheet (elastic contraction body) 3 along the inner wall surface 21, and is fed from the injection pipe 22 between the elastic sheet 3 and the inner wall surface 21. The pressurizing medium 4 enters. The peripheral edge of the elastic sheet 3 is wound and fixed inside the upper mold 2. In addition, in the upper mold 2, the elastic sheet 3 is pierced through the portion corresponding to the mouth end surface of the molded product, and a molding material injection port having a diameter of 10 mm is formed at six positions (only one position is shown in the figure).
Is provided.

In FIG. 1, 6 is an injection pipe for the molding material. Then, while the heated water is passed through the heater tube 12, the mold surface temperature of the lower mold 1 is kept at 50 ° C., and six injection ports 5 are provided in the mold cavity formed by the lower mold 1 and the upper mold 2. To 20 ° C, 20 ° C, 30 ° C, 40 ° C, 50 ° C with a molding compound of the following composition preset at 20 kg / cm ²
With the injection pressure of 1 and the drain hole 1 of the lower mold 1.
Excess moisture of the molding material was sucked by a suction pressure of 1 to -600 mmHg. Then, the pressurizing medium 4 is further press-fitted between the elastic sheet 3 and the upper mold 2 at a pressure of 30 kg / cm ² , and the molding material is pressed through the elastic sheet 3 to suck the water from the water draining hole 11 and further excess moisture. Was dehydrated and the desired shaped article was molded.

[Mixing of molding material] Ordinary Portland cement (manufactured by Ube Industries, Ltd.) 100 parts by weight Vinylon fiber (RM182 × 3 mm manufactured by Kuraray Co., Ltd.) 2 parts by weight Water 500 parts by weight

(Embodiments 6 to 9) With the mold surface temperature kept at room temperature, 20 ° C. and 30 ° C. from 6 inlets 5 in the mold cavity.
A desired shaped article was molded in the same manner as in Examples 1 to 5 except that molding materials having the following compositions whose temperatures were previously set to 40 ° C and 50 ° C were press-fitted.

(Comparative Example 1) A desired shaped article was molded in the same manner as in Examples 1 to 5 except that the temperature of the molding material injected from the injection port 5 was set to 60 ° C. (Comparative Examples 2 and 3) Examples 6 to 9 described above except that the temperature of the molding material injected from the injection port 5 was 10 ° C or 60 ° C.
A desired shaped article was molded in the same manner as in.

The dehydration time and the molding time when the shaped articles were molded in the above Examples 1 to 9 and Comparative Examples 1 to 3 were examined, and shown in Table 1 together with the viscosity of the molding material at the time of injection into the mold cavity. .

[0026]

[Table 1]

From Table 1 above, as in the molding method of the present invention, the molding material is preheated to 20 to 50 ° C., or the molding die is heated to heat the molding material in the molding die. It can be seen that if this is done, the viscosity of the molding material can be kept moderate, dehydration can be efficiently achieved, and a dense shaped article can be obtained.

The molding method according to the present invention is not limited to the above embodiment. For example, in the above-described embodiment, even when the molding die is molded at room temperature, the molding apparatus A including the heater tube 12 is used, but the conventional molding apparatus without the heater tube 12 is used. I do not care.

[0029]

EFFECTS OF THE INVENTION Since the method and apparatus for molding a hydraulic inorganic molded article according to the present invention are configured as described above, the viscosity of the molding material in the mold cavity can be appropriately maintained and the dehydration can be efficiently performed. As a result, the dehydration time can be shortened, and a more precise shaped object can be obtained. That is, a high-strength cured product useful as a building material can be produced with high productivity.

[Brief description of drawings]

FIG. 1 is a sectional view showing an embodiment of a molding apparatus for a hydraulic inorganic molded product according to the present invention.

[Explanation of Codes] A molding apparatus 1 lower mold (first split mold) 2 upper mold (second split mold) 3 elastic sheet 4 pressurizing medium 11 drainage hole 12 heater pipe (heating means) 21 inner wall surface 22 injection pipe

Claims (2)

[Claims] 1. A first split mold in which a large number of water drainage holes are formed in a wall surface and a second split mold in which an airtight elastic sheet is provided along the inner wall surface with its peripheral edge integrated, are closed. After pressing the hydraulic inorganic molding material into the mold cavity formed by
A pressurizing medium is press-fitted between the elastic sheet and the inner wall surface of the second split mold to compress the hydraulic inorganic molding material through the elastic sheet, and the suction is performed from the drain hole of the first split mold to the mold cavity. In the molding method of the hydraulic inorganic molded material in which the excess water of the hydraulic inorganic molding material inside is dehydrated out of the mold into a desired shape by performing a press-in dehydration step, the temperature of the hydraulic inorganic molding material inside the mold cavity Is adjusted to 20 to 50 ° C., a method for molding a hydraulic inorganic molded article. 2. A first split mold having a large number of drain holes for dehydrating excess water of the shaped object and an elastic sheet having airtightness are provided along the inner wall surface with their peripheral edges integrated. The pressurizing medium can be injected between the elastic sheet and the inner wall surface, and
A hydraulic inorganic substance having a second split mold which is closed with the split mold to form a mold cavity of a desired shape, and an injection port of the hydraulic inorganic molding material to the mold cavity is provided on the second split mold side. A molding apparatus for molding a hydraulic inorganic molded article, characterized in that the first split mold is provided with heating means for heating a hydraulic inorganic molding material shaped in a mold cavity. .